Filter for filtering mutagens from an engine oil

ABSTRACT

A filter ( 2 ) for filtering mutagens from an engine oil, which filter ( 2 ) comprises a body ( 4 ), an inlet ( 12 ) for oil passing into the body ( 4 ), an outlet ( 14 ) for the oil passing out of the body ( 4 ), and a filter ( 2 ) material in the body ( 4 ) for filtering the oil as the oil passes through the body ( 4 ), and the filter ( 2 ) material being such that it comprises activated carbon ( 16 ) for removing the mutagens.

This invention relates to a filter for filtering mutagens from an engineoil.

BACKGROUND OF THE INVENTION

New and unused engine oil generally does not contain any mutagens. Asthe oil is used in an engine, the effect of the length of use of theoil, the pressure at which the oil is used, the temperature at which theoil is used, and water cause the creation of mutagens. Many of thesemutagens are toxic and they can cause fatal diseases such for example ascancer.

Known attempts to reduce the level of mutagens produced as engine oil isused, have simply been to recommend that engine oil is changed atfrequent intervals, for example at 6,000 mile intervals. I have nowestablished that recommended oil change intervals are too long and toxiclevels of mutagens will be present in the engine oil long beforerecommended oil changes. In addition, engine manufacturers areconstantly striving towards producing engines that require oil changesat longer intervals rather than shorter intervals.

It is an aim of the present invention to obviate or reduce the abovementioned problem.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the present invention provides a filter for filteringmutagens from an engine oil, which filter comprises a body, an inlet foroil passing into the body, an outlet for oil passing out of the body,and a filter material in the body for filtering the oil as the oilpasses through the body, and the filter material being such that itcomprises activated carbon for removing the mutagens and a retainermaterial for retaining the activated carbon in place, the activatedcarbon is activated particulate carbon, the activated carbon is separatefrom and not integrally formed with the retainer material, the activatedcarbon has substantially its entire surface available for contact withthe oil, the retainer material is a water-absorbent material, and theretainer material is in the form of a plurality of radially extendingadjacent layers or pieces with the activated carbon between the layersor pieces wherein the activated carbon extends radially to a depthdefined by the layers or pieces.

The provision of a filter for filtering the mutagens from the engine oilis of very substantial benefit. More specifically, the mutagens can befiltered from the engine oil as they are created. The filtered mutagenscan be retained in the filter where they will cause minimum healthproblems. The activated carbon is a substance having large molecules andthese large molecules are able to trap the mutagens. In addition, theactivated carbon is a relatively cheap material, and one that is able tobe achieved from natural sources. Thus the activated carbon itself isinexpensive to use so that it is able to meet commercial considerations,and the carbon is safe to use so that it is able to meet health andsafety considerations. Thus the filter of the present invention is ableto solve a considerable health problem in a cheap and failsafe manner.After use, the filter with the mutagens can be destroyed, for example byburning or any other suitable and appropriate method.

The filter of the present invention may be one which is simply forfiltering the mutagens from the engine oil. Alternatively, the filtermay be a multi-purpose filter for generally filtering the oil as it isused. If desired, the filter may be a multi-purpose filter for firstlyfiltering the mutagens from the engine oil, secondly for filtering theoil in a general manner, and thirdly for filtering the oil of any waterin the oil. In this latter instance, the part of the filter that filterswater from the oil may be effected by the use of a foam material suchfor example as a woven foam material or a polymer foam material. Wherethe foam material is a woven foam material, then this woven foammaterial may also be a polymer foam material.

Preferably, the filter is one in which the activated carbon is fineparticle activated carbon. Such fine particle activated carbon providesa large active surface area for filtering the mutagens.

Preferably, the activated carbon is 44 micron activated carbon. Theactivated carbon may be smaller or larger is size than 44 micron.Generally, increasing the micron size of the activated carbon reducesthe active surface area. Reducing the size of the activated carbon maymake the activated carbon of such a small particulate size that specialhandling is required.

The retainer material may be a woven foam material and/or a polymer foammaterial.

The retainer material may be an absorbent fibre material. A preferredabsorbent fibre material is a polyacrylate super absorbent fibrematerial. Such a polyacrylate super absorbent fibre material is made byTechnical Absorbents Limited of Grimsby, United Kingdom under the nameOasis. The absorbent fibre material may be in the form of a non-wovenmaterial, a yarn material or a woven material.

The filter may be one in which the filter material forms part of acartridge which is positioned in the body. The cartridge may be adisposable cartridge which then enables the cartridge to be removed fromthe filter and destroyed, for example by burning, as and when required.

The cartridge may include a support member for the filter material.

The support member may have a plurality of apertures along its lengthfor enabling the oil to pass through the support member.

In one embodiment of the invention, the foam material is positionedaround the outside of the support member. In this embodiment of theinvention, the foam material is preferably in sheet form and it iswrapped around the outside of the support member.

In an alternative embodiment of the invention, the foam material ispositioned inside the support member. In this case, the foam materialmay be in sheet form or in the form of pieces. The filter may includeend screen members for retaining the foam material in the supportmember.

The filter of the present invention may be used with substantially allengines such for example as petrol engines, liquid petroleum gas (LPG)engines and diesel engines. The engines may form part of moving vehiclessuch for example as road vehicles in the form of cars, lorries, busesand motor cycles. Alternatively the engines may be in the form oftractors or earth moving equipment. The engines may also be in staticequipment such for example as electrical generators and pumps.

Where the filter uses replaceable cartridges, then new cartridges cansimply be placed in the body of the filter. If desired, a pack may besold with the filter comprising the body, the inlet and the outlet, anda plurality of the disposable cartridges for use in the same body. Ifdesired however the cartridge could be a permanent cartridge.

The filter may include a non-return valve. The non-return valve may bepositioned in an end part of the filter.

The filter of the present invention may be of any suitable andappropriate construction. The body of the filter may be made of aplastics material. Any suitable and appropriate plastics materials maybe employed. The plastics materials may be transparent for see-throughpurposes, or non-transparent. The body of the filter may also be made ofa metal.

The filter may be one having a separate inlet and outlet. The separateand outlet are preferably formed for push-on hose connections held inplace by clips such as jubilee clips. Other formations may be employedso that, for example, the separate inlet and outlet may be for receivingscrew fittings or snap fittings. The filter may alternatively have asingle combined inlet and outlet, and such a filter may be one in whichthe combined inlet and outlet is an internally threaded aperture forenabling the filter to be a screw threaded connection to an oil circuit.

It may be advantageous to know when the filter is blocking or a systemcontaining the filter is blocking, this being especially so when thefilter is a multi-purpose filter for generally filtering engine oil inaddition to filtering the engine oil of the mutagens. Pressure sensingmeans such for example as a pressure differential gauge can be utilisedso that a user can constantly monitor conditions.

The filter can be made in a wide variety of shapes. This can beadvantageous in enabling the filter to be made in a shape, for example astar shape, that gives an oil cooling function. With such a shape, thefilter can act as an oil cooler. With sufficient oil cooling from thefilter, hitherto used radiators could be reduced in size or evendispensed with.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Embodiments of the invention will now be described solely by way ofexample and with reference to the accompanying drawings in which:

FIG. 1 is an exploded view of a first oil filter;

FIGS. 2 and 3 are perspective and end views of a base part of the filtershown in FIG. 1;

FIG. 4 is a perspective view showing the inside of a cap part of thefilter shown in FIG. 1;

FIG. 5 is a perspective view of a support member forming part of thefilter shown in FIG. 1;

FIG. 6 is a perspective view of an alternative design of support memberto that shown in FIG. 5 and for use in the different filter;

FIG. 7 is a side view of the support member shown in FIG. 6;

FIG. 8 is a cross section through a second filter;

FIG. 9 is a perspective view of the filter shown in FIG. 8;

FIG. 10 shows two charts relating to the testing of liquid petroleum gasand petrol for mutagens after predetermined use periods; and

FIG. 11 shows a chart illustrating the advantages of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-5, there is shown a filter 2 for filtering mutagensfrom an engine oil. The filter 2 comprises a body 4 which is in twoparts and comprises a base 6 and a cap 8. The cap 8 has a screw threadedportion 10 for screwing into the base 6.

The body 4 has a plurality of inlets 12 in the base 6 for enabling theoil to pass into the body 4. The body 4 has an outlet 14 in the base 6for enabling the oil to pass out of the body 4.

The filter 2 comprises a filter material in the body 4. This filtermaterial is for filtering the oil as the oil passes through the body 4.The filter material is such that it comprises activated carbon forremoving the mutagens that are in the engine oil and that are createdduring use of the engine oil.

In FIG. 1, the activated carbon is shown as activated carbon 16 providedon a retainer material 18. The retainer material 18 is woven foammaterial which is in sheet form as shown and which has been wound arounda support member 20 in the form of a spool. The support member 20 has aplurality of apertures 22 along its length for enabling the oil to passthrough the support member 20. The retainer material 18 is wound aroundthe outside of the support member as shown and it is retained inposition by flanges 24, 26 on the support member 20.

FIGS. 6 and 7 show an alternative support member 28 which may be used inan oil filter (not shown) and one having a longer body than the body 4shown in FIG. 1. The support member 28 has apertures 22 and flanges 24,26 in the same manner as the support member 20.

FIGS. 8 and 9 show a second filter 32 comprising a body 34, an inlet 36for oil passing into the body 34, an outlet 38 for oil passing out ofthe body 34, and filter material 40 in the body 4 for filtering the oilas the oil passes through the body 34. The filter material 40 is suchthat it comprises activated carbon for removing the mutagens from theengine oil during use of the engine oil. The filter material 4 may besuch that it comprises a woven polymer foam material, with the activatedcarbon in place. The foam material 40 is in small pieces as shown.

The body 34 is made of a plastics material. The body 34 comprises a mainbody part 42 and a cap part 44 which screws to the main body part 42 viascrew threads 46. The cap part 44 has a grip portion 48 for helping thecap part 44 to be tightened and untightened from the main body part 42.An oil seal 50 is provided for preventing loss of oil from between themain body part 42 and the cap part 44 when the oil filter 32 isoperating under hydraulic pressure. The main body part 42 and the cappart 44 may be made as mouldings, for example from glass reinforcednylon.

The oil filter 32 may include a non-return valve (not shown). Twoscreens 46 are positioned as shown in order to retain the pieces of thefoam material 40 in the body 34.

Referring now to FIG. 10, there are shown two charts, one for liquidpetroleum gas and the other for petrol. The two charts show the effectof activated charcoal on mutagenicity of engine oil.

Petrol engine oil is shown to be mutagenic in the presence and absenceof liver S9 metabolic activation. The effect was tested of activatedcharcoal on the mutagencity of a petrol engine oil sample without theliver S9. Charcoal was mixed with the oil and DMSO (equal volumes) andafter sedimenting the charcoal, 100 microliters of supernatant weretested. The results are given below.

Number of revertants (mutagenicity) Sample S. typh. TA98 Negativecontrol 20, 23, 30 Oil − charcoal treatment 113, 100, 105 Oil + charcoaltreatment 23, 26, 24

FIG. 10 illustrates the testing of two engine oil samples formutagenicity in Salmonella typhimurium strain TA98 as DMSO/oilemulsions. Tests were in triplicate with a range of concentrations.

-   -   1. LPG with polymer, c.a. 4000 miles    -   2. Petrol with polymer, c.a. 2000 miles

Both samples gave a dose—response both with and without a metabolicactivation system.

This indicates that both samples contained mutagens. The values werehigher when a metabolic activation system was present.

FIG. 11 shows a chart for a with-charcoal treatment and awithout-charcoal treatment. The advantages of the use of charcoal canclearly be seen.

It is to be appreciated that the embodiments of the invention describedabove with reference to the accompanying drawings have been given by wayof example only and that modifications may be effected. Thus, forexample, the shape of the filters shown in the drawings may be varied.The filter of the present invention may be a special purpose filter justfor filtering mutagens from an engine oil. Alternatively, the filter maybe a multi-purpose filter for filtering the mutagens and other thingsfrom the engine oil. With such a multi-purpose filter, the filter mayfilter mutagens and general particles that are currently filtered withknown filters. Alternatively, the multi-purpose filter may be forfiltering the mutagens, and also the known particles/contaminants as arefiltered in standard filters, and if desired, water from the oil if anappropriate water-absorbing material is employed. Such an appropriatewater-absorbing material may be a woven foam material or a polymermaterial. One presently preferred such material is that manufactured bythe Camelot Company of Canada. The foam material does not become wet inhumid atmospheres and so there is no need to protect the foam material,for example by encapsulating it, from the effects of the atmosphere.Another presently preferred material is a polyacrylate super absorbentfibre material manufactured by Technical Absorbents Limited of Grimsby,United Kingdom under the name Oasis. A less preferred foam materialwhich can be used and which is in fact hygroscopic is that sold underthe trade mark Luquafleece by BASF Superabsorbents Ltd. of Birkenhead,United Kingdom.

1. A filter for filtering mutagens from an engine oil, which filtercomprises a body, an inlet for oil passing into the body, an outlet foroil passing out of the body, and a filter material in the body forfiltering the oil as the oil passes through the body, and the filtermaterial being such that it comprises activated carbon for removing themutagens and a retainer material for retaining the activated carbon inplace, the activated carbon is activated particulate carbon, theactivated carbon is separate from and not integrally formed with theretainer material, the activated carbon has substantially its entiresurface available for contact with the oil, the retainer material is anabsorbent material, and the retainer material is in the form of aplurality of radially extending adjacent layers or pieces with theactivated carbon between the layers or pieces wherein the activatedcarbon extends radially to a depth defined by the layers or pieces.
 2. Afilter according to claim 1 in which the activated carbon is 44 micronactivated carbon.
 3. A filter according to claim 1 in which the retainermaterial is a woven foam material.
 4. A filter according to claim 1 inwhich the retainer material is a polymer foam material.
 5. A filteraccordingly to claim 1 in which the retainer material is an absorbentfibre material.
 6. A filter according to claim 5 in which the absorbentfibre material is a polyacrylate super absorbent fibre material.
 7. Afilter according to claim 5 in which the absorbent fibre material is inthe form of a non-woven material, a yarn material or a woven material.8. A filter according to claim 1 in which the filter material forms partof a cartridge which is positioned in the body.
 9. A filter according toclaim 8 in which the cartridge includes a support member for the filtermaterial.
 10. A filter according to claim 9 in which the support memberhas a plurality of apertures along its length for enabling the oil topass through the support member.
 11. A filter according to claim 9 inwhich the filter material is positioned around the outside of thesupport member.
 12. A filter according to claim 11 in which the filtermaterial is in sheet form and is wrapped around the outside of thesupport member.
 13. A filter according to claim 9 in which the filtermaterial is positioned inside the support member.
 14. A filter accordingto claim 13 in which the filter material is in sheet form or is the formof pieces.
 15. A filter according to claim 14 and including end screenmembers for retaining the filter material in the support member.
 16. Afilter according to claim 1 and including a non-return valve.
 17. Afilter according to claim 16 in which the non-return valve is positionedin an end part of the filter.
 18. A filter according to claim 1 in whichthe outlet is an internally threaded outlet for enabling the filter tobe a screw threaded connection to an oil circuit.